シンプルな雲

https://gyazo.com/8d126a850b4939d4904d5bfc39a0574e

code:cloud.cpp

# include <Siv3D.hpp> // Siv3D v0.6.16

// 雲を表現するためのCircleの配列を作る

void MakeCloudCircles(Array<Circle>& cloudCircles, int n, double baseCenterY, double radiusScale = 1.5)

{

const double r = static_cast<double>(Scene::Width()) / n / 2 * radiusScale;

cloudCircles.clear();

for (int i = 0; i < n + 2; ++i)

{

const Vec2 basePos{ r + (i - 1) * Scene::Width() / n, baseCenterY };

// x,y,rを適当にずらす

cloudCircles << Circle{

basePos + Vec2{ Random() * r * 0.3, Random() * r * 0.5 },

r + Random() * r * 0.5

};

}

}

void MakeCloudCirclesArray(Array<Array<Circle>>& cloudCircles, int n, double radiusScale = 1.5)

{

{

const double margin = 250.0;

MakeCloudCircles(c, n, margin + (Scene::Height() - margin) / 3 * index, radiusScale);

}

}

void DrawCloud(Array<Array<Circle>>& cloudCircles, const ColorF& bgColor)

{

{

const ColorF color = bgColor.lerp(ColorF{ 1.0 }, 0.5 + 0.49 / 2 * ic);

for (const auto& circle : cloud)

{

circle.draw(color);

}

Quad{

Vec2{ cloud.front().x, cloud.front().y },

Vec2{ cloud.back().x, cloud.back().y },

Scene::Rect().br(),

Scene::Rect().bl() }.draw(color);

}

}

void Main()

{

const ColorF bgColor{ 0.6, 0.7, 0.8 };

Scene::SetBackground(bgColor);

const int N = 8;

// 雲 (Array<Circle>)

// 何層か重ねる

Array<Array<Circle>> cloudCircles{ 3 };

MakeCloudCirclesArray(cloudCircles, N);

while (System::Update())

{

if (KeyR.down())

{

MakeCloudCirclesArray(cloudCircles, N);

}

// 背景

Scene::Rect().draw(Arg::top = bgColor, Arg::bottom = bgColor.lerp(ColorF{ 1.0 }, 1.0));

// 雲

DrawCloud(cloudCircles, bgColor);

}

}